Incandescent electric lamp



(No Model.)

J. W. PACKARD. INOANDESGENT ELECTRIC LAMP.

No. 426,055 Patented Apr. 22. 1890.

MQQWM UNITED STATES PATENT OFFICE.

JAMES IVARD PACKARD, OF NEIV YORK, N. Y., ASSIGNOR TO TIIE \VEST- INGHOUSE ELECTRIC COMPANY, OF PENNSYLVANIA.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 426,055, dated April 22, 1890.

Application filed December 7, 1889- Serial No: 332,884. (No model.)

T0 00% whom it may concern.-

Be it known that 1, JAMES W. PACKARD, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Incandescent Electric Lamps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention consists in the improved construction of incandescent electric lamp hereinatter to be described and claimed.

In the drawings, Figure 1 represents the lamp with the carbon filaments, the electrodes, and the stock or support for said electrodes in place. Fig. 2 is a cross-section through the stock or support, showing the electrodes and their connections.

Heretofore in the construction of high-candle-power electric lamps Where two or more carbon filaments are used it has been customary to mount the four or more electrodes, to which said carbon filaments must be connected, in separate tubes, which have been scaled into a large closed tube of a diameter nearly equal to that of the base of the lamp. This tube of larger diameter then had to be sealed into the base of the lamp by a blown seal, which was very difficult and costly, and the resulting construction was cumbersome and awkward.

In my invention the lamp bulb A is blown with its base 13 in the same shape and way as is done in lamps of smaller size and ordinary candle-power. The electrodes are then mounted in a glass stock or support, which has the central stem C and four or more branches ff (1 d. The central stem of this stock or support can be sealed into the base of the lamp by an ordinary fiat seal, which is rapidly made and at little cost.

In the preferred form of my invention the central stem C is made solid, and the platinum electrodes are embedded solidly in the glass and connected together by loops, shown in Fig. 1, or 0therwise,so as to be in multiple arc. The branches (1 d ff, on the other hand, are preferably tubular in form, as shown in Fig. 2. The copper extensions E E, which are cemented or otherwise con nected with the platinum electrodes after the latter have entered the tubular portion of the branches, extend through these tubular branches. The extremities of these copper electrodes are again connected to short branches of platinum e e to facilitate the cementation of the electrodes to the carbon filament.

The two carbon filaments I I shown in Fig. 1 are connected to the four ends of the electrodes, so that the current entering by one of the electrodes D and leaving by the other electrode D will be equally divided between said filaments. In other words, said filaments and their connections to the electrodes are in multiple one with another.

The advantages of my invention are obvious, in that it furnishes a neat construction, which can be produced at a cost much less than the old form. The short central stem C being made solid, there is little or no danger of imperfections in scaling to the base 13 of the lamp or of its breaking after being put in place. The platinum electrodes embedded in this portion will expand at the same rate as the glass under the well-known law. The extensions of said electrodes, however, in the tubular branches are free to expand independently of the glass, and consequently can be made of copper at a great saving in cost.

IIaving therefore described my invention, what I claim as new, and desire to protect by Letters Patent, is-

1. In an incandescent electric lamp, a stock for supporting the electrodes of said lamp, which consists of the solid central stem of suchsize that it can be joined to the base of the lamp by a fiat seal, combined with four or more tubular branches from said solid central stem, together with the platinum elcc trodes embedded in the solid stem, and the copper extensions to the same, located in the tubular branches, substantially as described.

2. In an incandescent electric lamp, a stock for supporting the electrodes of said lamp,

which consists of the solid central stem of ing connected up in multiple are, substansuch size that it can be joined to the base of t-ially as described. TO the lamp by a flat seal, combined with four 111 testimony whereof I affix my signature or more tubular branches from said solid cenin presence of two witnesses.

5 tral stem, together With the platinum elec JAMES VARD PACKARD.

trodes embedded in the solid stem, and the WVitnesses: copper extensions to the szune, located in the J. A. VANDEGRIFT,

tubular branches, the platinum electrodes be- G. BOOTH. 

